LeetCode--182.寻找重复的电子邮箱

建表

Create table If Not Exists Person (Id int,Email varchar(255));
Truncate table Person;
insert into Person (Id, Email) values ('1','[email protected]');
insert into Person (Id, Email) values ('2','[email protected]');
insert into Person (Id, Email) values ('3','[email protected]');

根据邮箱分组统计，个数大于1

select Email, count(1)
 from person
 GROUP BY Email
 HAVING count(1) > 1